I've been interested in a sleep tracker for some time, so it's interesting (and logical) to hear rumours that it's a part of Apple's thinking for the mythical iWatch. One thing's clear though: If it's going to spend all night tracking my sleep, and all day tracking my walking, it's going to need one hell of a battery. When do I get to charge it?

Tracking sleep patterns is one area that has been a focus for some of the popular fitness tracking products on the market such as the FitBit and could be one feature Apple attempts to incorporate into iWatch. The FitBit products, for example, are capable of tracking movements to provide data on sleep patterns and calculate sleep efficiency. It also offers the ability to silently wake the user through vibrations without disturbing others. There are also a number of third-party iPhone connected devices and apps designed to improve and track sleeping habits.